Alternating current (AC) generators are used for myriad applications, for example, in a gas turbine engine, such as that found in aircraft, ships, and some terrestrial vehicles. These generators may include three separate brushless generators, namely, a permanent magnet generator (PMG), an exciter, and a main generator. Each of these generators may include rotors and stators. When the rotors rotate, AC current is induced in the associated stators. The AC current induced in the main generator stator is supplied to an electrical distribution system within, for example, the aircraft, ship, or terrestrial vehicle.
Many AC generators, such as the one described above, include one or more current transformers (CTs). The CTs sense, for example, the AC current in the main generator stator windings, and supply a signal representative of the AC current to a protection, monitor, and/or control circuit. These one or more circuits, using the signals from the CTs, may implement overload protection and/or generator control. Thus, the generator CTs are subjected to various tests upon installation to verify proper installation and operation.
Although current devices and methods for verifying proper installation and operation of generator CTs is safe, reliable, and accurate, these current devices and methods do suffer certain drawbacks. For example, with the exception of a “bench test” to verify resistance, the current devices and methods only allow CT verification testing to be conducted during generator functional testing, which is typically conducted after the generator is in a relatively high state of assembly. Thus, if the verification testing indicates that one or more of the CTs may be faulty, inoperable, or improperly installed, the generator may need to be substantially disassembled to correct the CT installation or replace the faulty CT, and then reassembled to once again conduct the CT verification testing. This can potentially result in increased labor time, which can concomitantly result in increased costs.
Hence, there is a need for a device and method of verifying proper CT installation and operation that does not rely on the generator (or other system) to be in a state of relatively high assembly. The present invention addresses at least this need.